1. Field of the Invention
The present invention relates to the improved reaction of gas phase reagents in a liquid which contains slurried solid catalyst particles. The invention is especially useful for the production of propylene oxide by reaction of propylene, oxygen and hydrogen in a slurry of noble metal promoted TS-1.
2. Description of the Prior Art
The production of propylene oxide by reaction of propylene, oxygen and hydrogen using a solid noble metal promoted TS-1 catalyst is by now, well known. See for example, Japanese Kokai No. 4-352771, U.S. Pat. No. 6,867,312, U.S. Pat. No. 6,710,192, U.S. Pat. No. 6,710,194 and the like.
It is often advantageous to carry out the reaction by contacting gaseous reactants in a slurry of solid catalyst particles in a suitable liquid such as methanol or methanol and water mixtures.
In such systems, for economic operation it is important that high reaction rates be maintained as well as high reaction selectivities to propylene oxide. It is also important that attrition of the slurried solid catalyst be maintained at a low level since excessive catalyst attrition causes operational problems and requires more frequent catalyst replacement.
Since the reaction is exothermic, it is also important that heat of reaction be efficiently removed from the reaction zone.